Make sure the students list is never tracked

The list of students that take this class should remain private.
Use logging for message severity handling

Log the runs to rotating files, using the logging module to redirect
messages to stdout, depending on their severity. The VERBOSE variable
controls the level of the stdout StreamHandler.
Comment & fix order of Exceptions, classes, funcs
Clarify how student ID's are extracted from URL's
Implement detection of failed logins
Add maintenance section, discussion of new logging